Novel method for synthesis of 3-hydroxy-1-phenyl-1,2,3,4- tetrahydroquinoline [5]

Full text of DOI:10.1007/s10593-006-0059-5

Chemistry of Heterocyclic Compounds, Vol. 42, No. 1, 2006
NOVEL METHOD FOR SYNTHESIS
OF 3-HYDROXY-1-PHENYL-
1,2,3,4-TETRAHYDROQUINOLINE
B. Barvainiene, A. Stanisauskaite, and V. Getautis
Keywords:
3-hydroxy-1-phenyl-1,2,3,4-tetrahydroquinoline,
N-(2,3-epoxypropyl)diphenylamine,
epichlorohydrin, cyclization.
When diphenylamine is heated with epichlorohydrin under pressure [1] or with addition of sodium
iodide at high temperatures [2], 3-hydroxy-1-phenyl-1,2,3,4-tetrahydroquinoline (1) is formed. In [3], it was
obtained by heating diphenylamine with excess epichlorohydrin at atmospheric pressure without a catalyst. The
same authors proved that formation of compound 1 occurs via N-(3-chloro-2-hydroxypropyl)diphenylamine [4].
We have observed that tetrahydroquinoline 1 can also be obtained in 53% yield from the epoxypropyl
derivative of diphenylamine.
O
OH
220–225 oC
N
N
1
When N-(2,3-epoxypropyl)diphenylamine synthesized by reaction of diphenylamine and
epichlorohydrin in the presence of KOH was distilled under vacuum, we noted formation of a byproduct with
melting point (78-79°C) corresponding to the melting point of the known compound 1 [3]. The optimal
cyclization temperature is 220-225°C; raising the temperature reduces the yield of the cyclization product 1. In
1
order to unambiguously establish its structure, we took the H NMR, IR, and mass spectra, since these data are
not available in the literature.
1
The H NMR spectrum was recorded on a Gemini-2000 (300 MHz), internal standard TMS. The IR
spectrum was taken on a UR-20 spectrometer in a KBr disk. The mass spectrum was recorded on a Waters
ZQ-2000 with direct injection of the sample. The course of the reaction was monitored by TLC on Silufol
UV-254 plates in a 1:4 acetone–hexane system. Silica gel L 40/100 (Chemapol) was used for column
chromatography.
__________________________________________________________________________________________
Kaunas University of Technology, Organic Chemistry Department, Kaunas LT-50270, Lithuania;
e-mail: brone.barvainiene@ktu.lt, albina.stanisauskaite@ktu.lt, vytautas.getautis@ktu.lt. Translated from
Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 138-139, January, 2006. Original article submitted
December 2, 2005.
0009-3122/06/4201-0123©2006 Springer Science+Business Media, Inc.
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3-Hydroxy-1-phenyl-1,2,3,4-tetrahydroquinoline (1). N-2,3-Epoxypropyl)diphenylamine (11.3 g,
0.05 mol) was heated at a temperature of 220-225°C under a nitrogen atmosphere for 30 h. When the reaction
was complete, the product was separated by chromatography. After removal of the eluent, the crystals formed
1
were filtered out and washed with ether. Yield 6 g (53.1%); mp 78-79°C (78.5-79.0°C [3]). H NMR spectrum,
δ, ppm (J, Hz): 7.41-6.66 (9H, m, Ar); 4.34-4.25 (1H, m, CH); 3.77-3.46 (2H, m, NCH2); 3.13 (1H, dd,
J
AB = 16.5, JAX = 4.4, ABX system, HA from CH2CH); 2.86 (1H, dd, JBX = 4.6, HB from CH2CH); 2.44-2.23 (1H,
br. s, OH). IR spectrum, ν, cm-1: 3280 (OH). Mass spectrum (chemical ionization, 20 V), m/z (Irel, %): 226
[M+H]+ (100), 208 [M+H–H2O]+ (90).
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4.
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W. Davies and W. Savige, J. Chem. Soc., 890 (1950).
H. H. Vorozhtsov, Jr. and S. I. Kutkevichus, Khim. Geterotsikl. Soedin., 374 (1965).
S. I. Kutkevichus and N. N. Vorozhtsov, Jr., Khim. Geterotsikl. Soedin., 549 (1965).
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